The present invention relates to push-button sensor switches and, more particularly, to a push-button sensor switch for controlling and indicating the output of a cooperating integrally mounted sensor element therein.
Push-button switches, including lighted switches, are well known and have been widely used in the art. A commercially highly successful improvement in the art of push-button switches has been the non-lighted, shuttered switch wherein a light reflecting signal surface is alternately exposed and concealed by the shutters in response to reciprocal movement of the button head which is mounted to the switch plunger. These switches provide a passive but dramatic indication of the operative switch position and otherwise avoid the need for a powered light bulb or other active indicating device, and have accordingly achieved substantial market acceptance. Switches of this type are exemplified in the U.S. Pat. to Schadow- No. 3,715,548, which is assigned to the same assignee as the present invention. These switches have also achieved significant market acceptance in the television and home products industry because of their cost and power savings, reliability, and physical attractiveness.
In this industry, light controlled resistor sensors have been provided on the control panel, or other suitable surface, of the television receiver. These sensors are used with associated utilization circuitry to automatically control the brightness levels of the picture tube, cathode ray tube (CRT), in response to varying levels of ambient illumination. That is, in a brightly lit room, a greater CRT intensity is required to provide desired levels of contrast. On the other hand, in a partially or fully darkened room, it has been found that reducing the intensity of the CRT tube is particularly desirable. Thus, these sensor systems function to provide an automatic brightness control.
To satisfy the needs of these sensor systems, separate switches, including push-button switches to control the output of the light sensors or the cooperating utilization circuitry have been proposed. This then provides the consumer with the option of utilizing the automatic brightness control selectively. That is, there are instances when it is desirable to override the function of the automatic brightness control as when an abnormal light condition exists in the viewing room. For example, a flickering or concentrated light source may prevail in the vicinity of the television receiver such that the unusual light source would adversely impact, or erroneously affect, the operation of the automatic brightness control.
It will be appreciated that the provision of a separate light sensor element, including the lens or other optics associated therewith, and a separate switch to control the operation thereof, suffers with the disadvantages of such multiplicity. Moreover, in a given product line, there are typically models which delete the structure of, and the functions provided by, these sensor devices or accessories for reasons of cost and other marketing considerations. Accordingly, several control panels must be provided to accommodate the different models, or the control panel bezel must be produced in a universal manner so as to accomodate the different models within a given product line. This has the disadvantages of increased tooling and inventory costs, and that the unused bezel openings must be suitably and attractively filled with compatible structure.
These and other disadvantages are overcome by the present invention wherein a non-lighted, shuttered and reciprocally operated push-button sensor switch is provided which controls and indicates the output of an integrally mounted sensor element by means of the cooperation between the switch housing, the mechanical shutters and the sensor element. The sensor switch, in accordance with the present invention, facilitates, notably, a controlled light sensitive resistor sensor which is particularly suitable for use in automatic brightness control systems for television receivers.